A computerized database generated from the literature on cytogenetic studies in couples experiencing repeated pregnancy losses has been set up at the University of Quebec at Chicoutimi. At the present time, it contains data on 22,199 couples (44,398 individuals). The statistical analyses showed a relationship between the distribution of the chromosome abnormalities and the number of abortions. An uneven distribution of the chromosomal structural rearrangements according to the sex of the carrier was found (P less than 0.05). Overall, 4.7% of the couples ascertained for two or more spontaneous abortions included one carrier. It also appeared that only translocations (both reciprocal and Robertsonian) and inversions were associated with a higher risk of pregnancy wastage. Therefore, genetic counselling should be offered to these couples and investigations performed on their extended families.